I ran into the same problem with Trezor Suite.  Annoyingly, there was no way to make it generate more addresses beyond the gap limit.  I guess the developers figured most folks wouldnt need more than 20 unused addresses or something. I get why they want clean standardized defaults. But a little customization would be nice! The only solution is to try a different wallet app with your Trezor.  Electrum lets you tweak the gap limit, so that could work.